Microbiology is the study of microorganisms, which are tiny living things that cannot be seen with the naked eye, such as bacteria, viruses, fungi, and protozoa. Microorganisms can be found everywhere, including in the soil, water, air, and inside other living organisms. Some microorganisms are helpful and necessary for life, such as those in our digestive system that help us break down food. However, some microorganisms can be harmful and cause diseases. Scientists in microbiology study these microorganisms to understand how they work, how we can use them, and how we can prevent and treat diseases caused by them.